In vitro and In vivo toxicity analysis of zinc selenium/zinc sulfide (ZnSe/ZnS) quantum dots

• Published in: Food and chemical toxicology Vol. 145; p. 111718
• Main Authors: Reshma, V.G., Sabareeswaran, A., Rajeev, K.S., Mohanan, P.V.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2020
• Subjects: Animals; Apoptosis; Body Weight - drug effects; Cell Line; Cell Survival - drug effects; Endocytosis - drug effects; Flow cytometry; HEK293 Cells; Humans; Kidney - drug effects; Kidney - pathology; Liver - drug effects; Liver - pathology; Lysosomal integrity; Mice; Organ Size - drug effects; Quantum dots; Quantum Dots - analysis; Quantum Dots - toxicity; Safety and toxicity; Selenium - analysis; Selenium - toxicity; Spleen - drug effects; Spleen - pathology; Sulfides - analysis; Sulfides - toxicity; Toxicity Tests; Zinc - analysis; Zinc - toxicity; Zinc Compounds - analysis; Zinc Compounds - toxicity; Flow cytometry; Safety and toxicity; Lysosomal integrity; Quantum dots; Apoptosis
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2020.111718

Despite the versatility of quantum dots (QDs) in optoelectronics and biomedical field, their toxicity risks remain a considerable hindrance for clinical applications. Cytotoxicity of Cadmium containing QDs is well documented and reveals that they are toxic to cells. Reports suggest that the presence of toxic elements at the QD core (e.g., cadmium, selenium) is responsible for its toxicity in in vivo and in vitro levels. Hence, here the toxicity of heavy metal free ZnSe/ZnS QDs on two scenarios were assessed, (i) HEK cells as in vitro system and (ii) Swiss Albino mice as in vivo model. Before toxicity analysis, QDs subjected to various optical and physico-chemical characterization methods such as absorption and emission spectra analysis, observation under U.V light, TEM, DLS, Zeta potential, FTIR, Raman and XPS spectra, ICP-OES, TGA and DTG curve. It is very necessary to characterize the synthesized QDs because their toxicity greatly influenced by the physico-chemical properties. On checking the vulnerability of HEK cells on exposure to ZnSe/ZnS QDs, the obtained results disclose that ZnSe/ZnS QDs showed merest impact on cellular viability at a concentration less than 100 μg/ml. Acute toxicity of 10 mg/kg ZnSe/ZnS QDs was studied in mice and no clinical or behavioural changes were observed. It did not induce any changes in haematological parameters and any loss of body or organ weight. Moderate pathological changes were evident only in the liver, all others organs like kidney, spleen and brain did not show any manifestations of toxicity. Current work lays substantial bedrock for safe biomedical and environmental application of ZnSe/ZnS QDs in near future. [Display omitted] •Green synthesis of ZnSe/ZnS QDs carried out via aqueous colloidal route.•Optical physicochemical characterization confirms authenticity of the QDs.•24 h exposure of 100 μg/ml ZnSe/ZnS QDs induced necrosis in HEK cells.•In vitro toxicity mainly due to the endocytosis of QDs.•No visible variation in in vivo parameters as part of 10 mg/kg dosage of QDs.